51166-71-3Relevant articles and documents
INCLUSION, COMPLEXATION AND EFFICIENT ENANTIOMERIC DISCRIMINATION BY REGIOSPECIFIC OVERMETHYLATION OF A DIMETHYL-β-CYCLODEXTRIN
Galons, Herve,Gnaim, Jallal,Rysanek, Nicole,LeBas, Genevieve,Villain, Francoise,Tsoucaris, Georges
, p. 181 - 184 (1993)
An unsymmetrically methylated β-cyclodextrin was prepared and allowed the chiral discrimination of the volatile included compound 1,7-dioxaspiro(5,5)undecane 1.
Cyclodextrin inclusion interferes with trolox oxygen radical scavenging capacity measurement
Sueishi, Yoshimi,Ishikawa, Misa,Hori, Masashi,Inazumi, Naoya
, p. 49 - 55 (2013)
The interference of cyclodextrin solubilization with the measurement of oxygen radical scavenging capacity was investigated. Cyclodextrin (CD) that can solubilize water-insoluble compounds has been used in the oxygen radical scavenging capacity assay called oxygen radical absorbance capacity (ORAC) method. A vitamin E analog, trolox (2-hydroxy-2,5,7,8-tetramethylchroman-2- carboxylic acid) has been employed as a standard compound in ORAC methods and the results were often expressed in the trolox equivalent unit. We found that trolox ORAC values measured with electron spin resonance-based ORAC method, were markedly dependent on the CD concentration, i.e., it decreased by 50% when [CD]/[Trolox]=100 was present. 2D ROESY NMR study of trolox/CD inclusion complex revealed that trolox resided within the CD cavity. The reactive phenoxyl group in trolox is shielded from the attack by the oxygen radical, suggesting that this hindrance was causal for the decrease in ORAC values. by Oldenbourg Wissenschaftsverlag, Mu?nchen.
Growth, shrinking, and breaking of pluronic micelles in the presence of drugs and/or β-cyclodextrin, a study by small-angle neutron scattering and fluorescence spectroscopy
Valero, Margarita,Dreiss, Cecile A.
experimental part, p. 10561 - 10571 (2011/01/12)
The associative structures between F127 Pluronic micelles and four drugs, namely, lidocaine (LD), pentobarbital sodium salt (PB), sodium naproxen (NP), and sodium salicylate (SAL), were studied by small-angle neutron scattering (SANS). Different outcomes for the micellar aggregates are observed, which are dependent on the chemical nature of the drug and the presence of charge or otherwise: the micelles grow with LD, are hardly modified with PB, and decrease in size with both NP and SAL. The partition coefficient, determined by fluorescence spectroscopy, is directly correlated to the amount of charge, following NP ≈ SAL a slightly deeper localization of LD and more superficial for PB. All drugs can form inclusion complexes with heptakis(2,6-di-O-methyl) β-cyclodextrin (hep2,6 β-CD). Hep2,6 β-CD, as shown in previous studies (Joseph, J.; Dreiss, C. A.; Cosgrove, T. Langmuir, 2008, 24, 10005-10010; Dreiss, C. A.; Nwabunwanne, E.; Liu, R.; Brooks, N. J. Soft Matter, 2009, 5, 1888-1896), is also able to form a complex with F127, resulting in micellar breakup. In the ternary mixtures, a fine balance of forces is involved, which results in drastic micellar changes, as observed from the SANS patterns. Depending on the ratio of drug, polymer, and hep2,6 β-CD and the nature of the interactions (which is directly linked to the drug chemical structure), the presence of drug either hinders micellar breakup by β-CD (at high enough concentration of LD or PB) or leads to micellar growth (NP). These effects are mainly attributed to a preferential drug/β-CD interaction (except for PB), which, at least in the conditions studied here, explains the higher β-CD concentration needed for micellar breakup to occur.
Catenated Cyclodextrins
Armspach, Dominique,Ashton, Peter R.,Ballardini, Roberto,Balzani, Vincenzo,Godi, Anna,et al.
, p. 33 - 55 (2007/10/02)
A novel synthetic approach is described for the construction of catenanes in aqueous solution from a partially methylated cyclodextrin (CD)-namely, heptakis(2,6-di-O-methyl-β-cyclodextrin) (DM-β-CD)- and a range of substrate molecules that contain a hydrophobic central core in the form of a 4,4'-disubstituted biphenyl unit (usually bitolyl) carrying two hydrophilic polyether side chains terminated by primary amine functions.In water, the amphiphilic catenane precursors form 1:1 complexes with β-CD and DM-β-CD and 2:1 (guest:host) complexes with the larger γ-CD.Macrocyclizations of the biphenyl-containing substrates with aromatic diacid chlorides in aqueous solution and in the presence of DM-β-CD under Schotten-Baumann conditions afforded - in low yields - a range of - and catenanes.When a consitutionally asymmetrical diamine was employed as the substrate, orientational isomers of a catenane were obtained.A catenane incorporating a macrocyclic tetralactam was found to exist as a mixture of head-to-head and head-to-tail isomers, which could be separated by high pressure liquid chromatography and identified unambiguously by nuclear magnetic resonance spectroscopy.One of the catenanes afforded good single crystals from which the solid state structure was determined by X-ray crystallography.Other techniques which aided the characterization of these novel compounds included ultraviolet/visible and luminescence spectroscopy, dynamic nuclear magnetic resonance spectroscopy and fast atom bombardment mass spectrometry.Generally speaking, the catenated cyclodextrins are soluble in halogenated and aromatic hydrocarbons as well as in hydroxylic solvents.The existence of these new compounds gives us a unique insight into the nature of the noncovalent bonding interactions that cyclodextrins employ in binding substrate molecules. - Keywords: catenanes * cyclodextrins * macrocycles * orientational isomerism
